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Introduction to Psychology - A Gateway to Mind and Behavior
The Book= =Chapter 1: Introduction to Psychology and Research Methods= Psychology - Behave Yourself! Behavior is anything that someone does. This can include ''overt behavior'', which is directly observable behavior, as well as ''covert behavior'', which is not as easily, directly externally observable, such as dreaming or thinking. Goals of Psychology: # '''Description''' of behavior: accurate record of scientific observations # '''Understanding''' behavior: identify the cause for a certain behavior # '''Prediction''' of behavior: forecast behavior as reliably as possible # '''Control''' behavior: alter the conditions which influence behavior Critical Thinking - Take it with a grain of salt The basic principles of critical thinking # There are few statements which can be deemed true ''without'' thorough scientific testing and analysis # Critical Thinkers are more occupied with falsifying beliefs and statements than with verifying them. This quest extends even to their own beliefs which will in the end make them more confident in their beliefs since they have survived a whole series of falsification attempts. # Never trust that something is true because an 'expert' says it is. Rather try and figure out whether the expert's argumentation is plausible and whether the evidence brought forward is convincing. # Always pay attention not only to the ''quantity'' but also to the ''quality'' of the evidence provided to sustain an argument # Always be open-minded but never to the point of becoming gullible, be prepared to think in entirely new ways, but don't be to easily convinced '''Uncritical Acceptance''' Taking something for the truth only because we want to believe that it is true or it would be desirable if it were so. '''Confirmation Bias''' When getting information (reading a text, listening to a podcast, watching the news), we tend to pick out the information which ''confirms'' our pre-existing assumptions '''The Barnum Effect''' The inclination to identify with personal descriptions when they are stated in general terms Scientific Research - How to think like a psychologist The six elements of the '''scientific method''' # Making observations # Defining a problem # Proposing a hypothesis (a possible explanation for a certain behavior) # Gathering evidence/ Testing the hypothesis # Theory building (theories establish relations between different concepts and facts, taking into account existing data and predicting future results) # Publishing results '''operational definition''' - names the exact procedures used to represent a certain otherwise intangible concept. That way covert behavior is defined in terms of overt behavior and by that can be tested and measured scientifically. A Brief history of psychology - Psychologies family album '''stimulus''' any physical impulse that has an effect on a person and evokes a response '''conditioned response''' a learned reaction to a certain stimulus ''Structuralism'' - the use of introspection to make deductions about sensations and perceptions ''Functionalism'' - mirroring the development of the theory of evolution in biology, the quest to find out how the mind contributed to adapting to an environment ''Behaviorism'' - based on the belief that all human responses are determined by stimuli alone ''Gestalt-Psychology'' - an all encompassing view of sensation and thought, regarding them as whole experiences, not broken into units ''Psychoanalytical Psychology'' - a large part of the mind and of the resulting processes takes part in the unconscious, a lot of which is repressed. every behavior has a cause, which can, however, not be found in external stimuli but rather in the unconscious. Freud as the father of this branch of psychology also created the first form of psychotherapy. Today ''psychodynamic theories'' are more common which represent a kind of legacy of Freud's approaches, they still emphasize the importance of internal processes and of the unconsciousness ''Humanistic Psychology'' - focus on subjective human experience, ideals, problems and potential. Belief in the free will of humans, the possibility to choose the direction life is going to take Psychology Today - Three complementary perspectives on Behavior ''Biological Perspective'' # Biopsychological View - behavior is the result of internal physical, chemical and biochemical processes, mechanistic perspective # Evolutionary View - behavior is the result of the process of evolution, mechanistic perspective ''Psychological Perspective'' # Behavioral View - behavior is shaped by the environment, mechanistic perspective # Cognitive View - behavior can be understood in terms of mental processes and information processing, computer-like perspective # Psychodynamic View - emphasizes internal processes and hidden and unconscious forces, pessimistic perspective # Humanistic View - behavior is directed by the self-image, subjective perceptions of the world and the personal need for growth, positive philosophical view ''Sociocultural Perspective'' # Sociocultural View - behavior is influenced by the social and cultural context, interactionist perspective The Psychology Experiment - Where Cause meets Effect The three steps of conducting a psychological experiment # '''Manipulate a condition''' which you suppose has a direct effect on behavior (this condition can also be referred to as variable) # Set up '''two or more groups''' of subjects which are exactly the same apart from the condition which is being manipulated (the ''experimental'' and the ''control'' group) # '''Record''' whether the manipulation did in fact have an impact on the behavior monitored The different types of variables # '''Independent variables''' are the conditions which are suspected to have an impact on the monitored behavior. They are manipulated by the experimenter. # '''Dependent variables''' is the behavior which is being monitored and on which the manipulated conditions are expected to have an impact. # '''Extraneous variables''' are all those conditions which the experimenter wants to prevent from having an effect on the result. → the experimental groups is exposed only to the independent variable and the control group to exactly the conditions except for the independent variable. By keeping the interfering extraneous variables away from both groups any difference in the dependent variable after the experiment must have been caused by the manipulation of the independent variable. This allows to establish a clear ''Cause and Effect'' relation. In order to obtain valid results they must be '''statistically significant''', which means that it has to be highly unlikely that the results obtained in the experiment were only obtained by chance or coincidence. To ensure a representative sample of people in both groups the assignment to both groups is '''randomized'''. '''Meta-Analysis''' - the synthesizing and analyzing of results of a series of previous studies. Double-Blind - On Placebos and Self-fulfilling prophecies '''Placebo Effect''', changes in behavior caused by the belief to have received a drug or any other form of medical treatment. (Placebos work by changing our expectations, we ''expect'' medicine to make us feel better and these expectations have for example been found to reduce the actual brain activity linked to pain, so the placebo effect cannot even be claimed to be purely imaginary) ''Research Participant Bias'' certain information about the experiment and their role in the experiment might affect the impact the manipulated condition has on participants because they develop expectiations. Solutions can be to not inform participants what the experiment is about and whether they are in the experimental or in the control group: '''single-blind experiment''' ''Researcher Bias'' the risk that researchers will tend to find what they expect to find in an experiment. To avoid both biases it is possible to conduct a '''double-blind experiment''' in which neither experimenter nor participants know who is in the experimental and who in the control group and who receives a real drug and who a placebo. Nonexperimental research methods - Different Strokes # ''The Experimental Method'', conducting controlled experiments. # ''The Naturalistic Method'', conducting active observation of behavior in its natural setting without any external influence or manipulation. This is first-off purely a descriptive method and further research is needed to establish cause and effect relations. One of the main traps of the naturalistic method is the '''observer effect''', which refers to changes in behavior of the observed caused by an awareness of the presence of the observer. This can be avoided by concealing the observer or making use of hidden recording devices. Furthermore, the '''observer bias''' might affect the result, which just as the researcher bias might lead the observer to only record observations which fit and fulfill expectations. Another bias that comes into play when observing animals is the '''antropomorphic error''' which refers to the attribution of human thoughts and emotions to animals in order to explain their behavior. # ''Correlational Method'', connecting two observations by a correlation. This is done by statistically measuring the correlation coefficient, denominating the grade of correlation between the observations. This is done with the '''Correlation Coefficient''', is a number somewhere between -1,00 and +1,00. Numbers close to 0 indicate a very weak or even non-existent correlation, +1,00 shows a perfectly positive correlation (an increase in one measure coincides with an increase in the other measure), -1,00 a perfectly negative correlation (an increase in one measure indicates a decrease in the other). → Correlation does not demonstrate Causation! # ''The Clinical Method'', working with patients in clinics or mental hospitals. Mostly conducting in-depth '''case studies'''. Since these studies lack control groups the generalized insights and explanations they can offer are limited. # ''The Survey Method'', conducts surveys with a '''representative sample''' of people, that is a sample of people which represents the larger population (= a group of animals or people belonging to the same category). Surveys can render quite accurate results but when the sample is biased the result is too, a ''biased sample'' is a sample which does not truly reflect the population it is meant to represent. Furthermore, surveys might be affected by the '''courtesy bias''' which tends to result in people answering questions in a way which is not truthful but rather socially and politically correct. =Chapter 2: Brain and Behavior= Neurons - Building a Bio-Computer The brain is made up of about 100 Billion '''neurons''' and the same number of '''glials''', cells assisting the neurons. Neurons carry ''input'' from the senses to the brain and ''output'' from the brain to the muscles. Most neurons have four parts: # The '''dendrites''', neuron fibers which receive signals from other neurons # The cell-body or '''Soma''', also receives messages from other neurons, but also sends messages itself # The '''Axon''', a thin fiber which passes on the messages from the soma # The '''Axon Terminal''', the bulb-shaped end of an axon which is connected to other neurons and allows information to flow between them In and around the neurons are '''Ions''', which may be '''positively''' or '''negatively''' charged. When a neuron is inactive, also called ''resting'' it has more negatively charged ions on its inside and more positively charged ions on the outside. The electrical charge of a resting neuron, called '''resting potential''' is about -60 to -70 millivolts at the Axon. The electrical charge of -50 millivolts is the threshold value above which the neuron will "fire", by sending an '''action potential''' down the axon to another neuron. Process inside the axon during an action potential: The axon is pierced by tiny holes all along its length. Normally they are closed by molecules functioning like gates, in the event of an action potential they open and let Na+ sodium ions rush into the axon (before, in the resting potential, the inside of the axon was negatively charged). The first gates open close to the soma and then they continue opening along the axon (just like dominoes, one gate after the opens). After each action potential, K+ potassium ions flow out of the membrane and the neuron briefly returns to its resting potential a status in which it is less inclined to fire. Some axons are coated over with '''myelin''', the layer has small gaps which help the impulses to move faster, since they don't have to move down the entire axon but can jump from gap to gap: '''saltatory conduction'''. → while nerve impulses are ''electrical'', communication between neurons is ''chemical''. '''Synapse''': the space between two neurons. When an action potential reaches the tip of an axon terminal, '''neurotransmitters''' are released into the synapctic cleft, these transmitters are chemicals which alter the activity of a neuron. They are received by the '''receptor sites''' either on the dendrites or on the soma of the receiving neuron, which are sensitive to neurotransmitters. There are different forms of neurotransmitters, made up of different chemicals, which belong to specific pathways in the brain. Some neurotransmitters ''excite'' the receiving neuron, making it more likely to fire and some ''inhibit'' it, making it less likely to fire. '''Neuropeptides''' regulate subtler brain activity by not carrying messages directly but instead ''regulating'' the activity of other neurons. '''Neural Networks''' are interlinked connections between neurons which process information in our brain. When a neuron receives various messages from other neurons, it combines all the messages and checks whether it has received sufficiently more exciting than inhibiting messages and only if that is the case, the neuron fires. '''Neuroplasticity''' describes the capacity of the brain to change in response to experience. → meaning synaptic connections might form but also other connections might weaken and die, this is exactly what happens when changing a habit, the old neural networks triggering the habitual action die while new networks for the new habit are formed. The Nervous System - Wired for Action '''Central Nervous System (CNS)''' is made up of the brain and the spinal cord. The spinal cord transport messages from the brain to the '''Peripheral Nervous System''', which is a network of ''nerves'' (large bundles of axons, most of which outside of the brain and the spinal cord are covered by a layer of '''neurilemma''') carrying messages to and from the spinal cord (31 nerve bundles in total and 12 cranial nerves, running directly from the brain and not through the spinal cord). A '''Reflex arc''' is an automatic response provoked by a stimulus which arises directly in the spinal cord without direction from the brain. Such stimuli are carried to the spinal cord by '''sensory neurons'''. Once arrived at the spinal cord, the sensory neuron links up with a '''connector neuron''' which has the principal function to connect two neurons with each other. This neuron then activates a '''motor neuron''', connected to muscles and glands. The fibers of the muscles are made up of '''effector cells''' capable of triggering a response. Even though the process of reflex occurs within the spinal cord and without intervention of the brain, the spinal cord usually informs the brain afterwards and so conscious responses may follow. The Peripheral Nervous System itself is divided into two parts # '''The Somatic Nervous System (SNS)''' which carries messages to an from the sense organs and skeletal muscles # '''The Autonomic Nervous System (ANS)''' which serves internal organs and glands. Directs mostly automatic processes. The ANS itself is divided into two parts, which are both related to emotion and involuntary actions ## '''The Sympathetic System''' - emergency system which arouses the body for action ## '''The Parasympathetic System''' - quiets the body and keeps vital body functions running '''neurogenesis''', the way in which the brain produces new brain cells. Daily thousands of neurons grow deep within the brain and then rise to the surface to become a new part of the brain circuit. Research Methods - Charting the brain's inner realms # '''CT''' (Computer Tomographic Scanning) an X-Ray Scan of the brain # '''MRI''' (Magnetic Resonance Imaging) a scanning of the brain of the entire body using a strong magnetic field which then creates a 3D Model of the scanned parts and shows much more details than a CT # '''ESB''' (Electrical stimulation of the brain), stimulation of the brain with a mild electrical current evoking instant responses by the body # '''EEG''' (Electroencephalograph) detects electrical activity near the surface of the brain and then records them. It can identify tumors and seizures as well as different states of the brain such as dreaming. # '''PET''' (Prositron Emission Tomography), measures positrons as they are emitted by glucose (sugar) as it is consumed by the brain. The brain works with sugar from which it gains its energy, thus, areas with more energy are the currently active areas. PETs can produce images of activity both near and below the surface of the brain # '''fMRI''' (functional MRI) uses the technique of an MRI scan to make brain activity visible The Cerebral Cortex - My, what a wrinkled brain you have! The human brain might not be the largest in absolute weight, but with the brain/body ratio of 1/60 it is exceptional in relative size, this ratio is possible due to the '''corticalization''' of the brain, meaning the way in which it is folded up and wrinkled so that it fits inside the skull. The brain essentially consists of the ''cerebral cortex'' which is divided into ''two hemispheres'' and they are again divided into a number of ''lobes''. The cortex largely consists of grey matter (brain tissue made up off cell bodies). '''Cerebral Hemispheres''', the two hemispheres of the brain are connected by a thick band of axons, the ''corpus callosum''. The two hemispheres underlie the principle of ''contralteral organization'', meaning that the right hemisphere is wired to the left side of the body and the left hemisphere to the right side of the body. Damage to one of the hemispheres might cause ''spatial neglect'', which causes disturbances in perception on one side. '''Split Brain''', in very extreme cases of epilepsy the corpus callosum can be cut in order to prevent short circuits in the brain. Afterwards two separate brains with their own perception exist within one skull. [http://www.nature.com/news/the-split-brain-a-tale-of-two-halves-1.10213 The Split Brain - a Tale of Two Halves] * The Left Hemisphere: usually responsible for all language related abilities, analytical capacities and complex movements. → it processes information ''sequentially'' * The Right Hemisphere: responsible for all perceptual skills, recognizing faces or patterns as well as expression emotions and recognizing emotions of others. The right side of the brain is not able to produce language in any sophisticated way but if it is damaged people loose the capacity to understand jokes, irony, sarcasm and the like. → it processes information ''holistically'' Frontal Lobes Are concerned with higher mental abilities and determine our sense of self. They also direct movement, all those motoric abilities are directed by the '''primary motoric cortex''', that is divided into areas dedicated to directing the movement of certain body parts. The size of the area dedicated to each body part is determined by the importance of the respective body part for motoric actions not by its size. The motor cortex contains a number of ''mirror neurons'' which are activated when the body performs a certain act but also when the act is only observed. It might be possible to explain our intuitive understanding of other people's behavior with these neurons and also how we learn behavior, since a specific neural network becomes activate when we observe an action and can subsequently be used to imitate this same action. The most part of the rest of the frontal lobes is commonly called frontal association area. This '''association cortex''' is dedicated to combining and processing information, it receives sensations from primary sensory experiences and then matches them up with memories to create percepctions. They can also contribute to other complex mental processes such as language, damage to the association cortex can lead to '''aphasia''' ''Recalled to Life'', Oliver Sacks, 'The Mind's Eye', 2010, pp. 52-75 , the inability to use language. If the damage is in '''Broca's Area''' it results in difficulties in speaking or writing, also referred to as ''motoric/expressive aphasia''. The front of the frontal lobes is referred to as '''prefrontal cortex''', it is related to complex behavior and damage to it may result in drastic changes in personality and emotional life → much of what is commonly understood as intelligence is related to activity in the prefrontal lobes Parietal Lobes The Parietal Lobes are dedicated to all types of bodily sensation. All these tactile sensation first enter the parietal lobes through the '''primary somatosensory cortex'''. Like in the case of the primary motoric cortex area sizes on the primary somatosensory cortex are distributed in relation to the importance of the body part for sensory experience. The Temporal Lobes The Temporal Lobes are responsible for all kinds of auditory reception, they are located at each side of the brain. Auditory signals are first received by the '''primary auditory cortex'''. The sensations are then passed on to the association cortex in the temporal lobes. One of the association areas on the left temporal lobe is called '''Wernicke's Area''', responsible for language association. If there is damage to this area the result is ''receptive aphasia'', meaning that language can still be expressed but it can no longer be understood. The Occipital Lobes The Occipital Lobes are dedicated to visual input and are located at the back of the brain. The first receiving area of visual sensation is the '''primary visual cortex'''. If the association areas of the occipital lobes are damaged a '''visual agnosia''' might result, which is the inability to perceive and identify objects. This might also extend to a '''facial agnosia''' which is the inability to recognize all faces even familiar faces. ''The Man who Mistook his Wife for a Hat'', Oliver Sacks, "The Man Who Mistook his Wife for a Hat", 1985, pp. 11-23; ''Sight Reading'', Oliver Sacks, "The Mind's Eye", 2010, pp. 17-50 =Chapter 3: Human Development= =Chapter 4: Sensation and Perception= =Chapter 5: States of Consciousness= =Chapter 6: Conditioning and Learning= =Chapter 7: Memory= =Chapter 8: Cognition, Language and Creativity= =Chapter 9: Intelligence= =References